Rails: How to pass array from view to controller with button_to - ruby-on-rails

Question

I'm new to rails. What I'm trying to do is to design an order system. It lists a bunch of items and each item is followed by a select box so that people can choose the number that they want to order. My question is how to pass this count[] array and the corresponding item id from view to controller using button_to. Thank you for any suggestions.
<% #items.each do |item| %>
<li>
<%= link_to item.name, item %>
<%= select_tag 'count[]', options_for_select([0,1,2,3,4,5])%>
</li>
<% end %>
<%= button_to 'Place Order', orders_confirm_path, method: :post, params: { ??? } %>

Answer 1

You use the tag multi-select.
example in your view. For can select multi with ctrl + click at item:
<%= form_tag orders_confirm_path, method: :post %>
<label>select more than one with ctrl + click at item</label>
<p><%= select_tag :items, Item.all.collect {|item| [item.name, tem.id]}, {prompt: "Select item"}, multiple: true %></p>
<p><%= button_to 'Place Order'%></p>
and your controller you can receive the parameters in this way:
def create
#order = Order.new(params[:items])
if #order.save
code ...
else
code ...
end
end

Answer 2

You can this using form like below
<%= form_tag orders_confirm_path, method: :post do %>
<% #items.each do |item| %>
<%= hidden_field_tag :item_id, value: item.id %>
<li>
<%= link_to item.name, item %>
<%= select_tag 'count[]', options_for_select([0,1,2,3,4,5])%>
</li>
<% end %>
<%= button_to 'Place Order' %>
<% end %>
Now you can find on controller params[:count] params[:item_id]
Hope to help